Sharing visual information during distributed collaboration can be challenging when the collaborators are not situated in an office environment and need a hands-free system for communication. In these work situations, conventional systems use a head mounted device (HMD) with front-facing camera and a wearable computer, which allows users to share their respective views with each other. A front-view video (pre-recorded or live-view) or a single snapshot can communicate visual information quite well; however, these conventional systems do not facilitate a user pointing things out in the shared video or snapshot, which would make the communication more precise and less open to critical misinterpretations.
New wearable computing devices such as Google Glass or Vuzix smart Glasses offer a new way of communicating with collaborators by easily taking and sharing personal views. As communicating with images is becoming widely accepted, images are by necessity accompanied by words, annotations and tags to convey a complete message. Several systems in existence today can be used for creating and retrieving annotations of signs and posters using Google Glass. However, in such systems, photos taken by the Glass' camera often have a wide-angle view to match the user's field of view, hence photos often capture peripheral objects that can distract from the message that the user wants to communicate. Previous research has shown that annotations that visually communicate referential information, simplify and disambiguate communication. However, wearable computing devices often have limited input methods, in particular, for adding precise markers in images. Thus, there is a need for a natural pointing mechanism that uses a wearable computing device for making annotations.